Plasma surface modification of the inner wall of a slender tube is quite difficult to achieve using conventional means. In the work described here, an inner coaxial radio frequency （RF） copper electrode is utilized ...Plasma surface modification of the inner wall of a slender tube is quite difficult to achieve using conventional means. In the work described here, an inner coaxial radio frequency （RF） copper electrode is utilized to produce the plasma and also acts as the sputtered target to deposit copper films in a tube. The influence of RF power, gas pressure, and bias voltage on the distribution of plasma density and the uniformity of film thickness is investigated. The experimental results show that the plasma density is higher at the two ends and lower in the middle of the tube. A higher RF power and pressure as well as larger tube bias lead to a higher plasma density. Changes in the discharge parameter only affect the plasma density uniformity slightly. The variation in the film thickness is consistent with that of the plasma density along the tube axis for different RF power and pressure. Although the plasma density increases with higher tube biases, there is an optimal bias to obtain the highest deposition rate. It can be attributed to the reduction in self-sputtering of the copper electrode and re-sputtering effects of the deposited film at higher tube biases.展开更多
This paper presents a novel method to fabricate separated macroporous silicon using a single step of photo-assisted electrochemical etching. The method is applied to fabricate silicon microchannel plates in 1 O0 mm p-...This paper presents a novel method to fabricate separated macroporous silicon using a single step of photo-assisted electrochemical etching. The method is applied to fabricate silicon microchannel plates in 1 O0 mm p-type silicon wafers, which can be used as electron multipliers and three-dimensional Li-ion microbatteries. Increasing the backside illumination intensity and decreasing the bias simultaneously can generate additional holes during the electrochemical etching which will create lateral etching at the pore tips. In this way the silicon microchannel can be separated from the substrate when the desired depth is reached, then it can be cut into the desired shape by using a laser cutting machine. Also, the mechanism of lateral etching is proposed.展开更多
基金Natural Science Foundation of China(Nos.10575025,10775036)City University of Hong Kong Applied Research Grants(Nos.9667002,9667011)
文摘Plasma surface modification of the inner wall of a slender tube is quite difficult to achieve using conventional means. In the work described here, an inner coaxial radio frequency （RF） copper electrode is utilized to produce the plasma and also acts as the sputtered target to deposit copper films in a tube. The influence of RF power, gas pressure, and bias voltage on the distribution of plasma density and the uniformity of film thickness is investigated. The experimental results show that the plasma density is higher at the two ends and lower in the middle of the tube. A higher RF power and pressure as well as larger tube bias lead to a higher plasma density. Changes in the discharge parameter only affect the plasma density uniformity slightly. The variation in the film thickness is consistent with that of the plasma density along the tube axis for different RF power and pressure. Although the plasma density increases with higher tube biases, there is an optimal bias to obtain the highest deposition rate. It can be attributed to the reduction in self-sputtering of the copper electrode and re-sputtering effects of the deposited film at higher tube biases.
基金Project supported by the International Collaboration Project of China(No.10520704400)PCSIRT,the National Natural Science Foundation of China(No.61176108)the City University of Hong Kong Strategic Research Grant,China(No.7008009)
文摘This paper presents a novel method to fabricate separated macroporous silicon using a single step of photo-assisted electrochemical etching. The method is applied to fabricate silicon microchannel plates in 1 O0 mm p-type silicon wafers, which can be used as electron multipliers and three-dimensional Li-ion microbatteries. Increasing the backside illumination intensity and decreasing the bias simultaneously can generate additional holes during the electrochemical etching which will create lateral etching at the pore tips. In this way the silicon microchannel can be separated from the substrate when the desired depth is reached, then it can be cut into the desired shape by using a laser cutting machine. Also, the mechanism of lateral etching is proposed.
